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00019 Two thousand years of atmospheric rare earth element (REE) deposition as revealed by an ombrotrophic peat bog profile, Jura Mountains, Switzerland
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all other plant groups are minor in comparison. Petrographically, the Sewickley coal contains high percentages of vitrinite (average 82.3%, mineral matter-free (mmf)), with structured forms being more common than unstructured forms. In contrast, liptinite and inertinite macerals both occur in low percentages (average 7.7% and lO.O%, respectively). Geochemically, the Sewickley coal has a moderate ash yield (average 12.4%) and high total sulfur content (average 3.4%). Four localities contained a high ash or carbonaceous shale bench. These benches, which may be coeval, are strongly dominated by tree fern spores, Unlike the lower ash benches, they contain low percentages of vitrinite, which mainly occurs as unstructured vitrinite, and higher liptinite and inertinite contents. The accumulated data suggest that the Sewickley paleomire was probably a rheotrophic, planar mire that had a consistent water cover. This is supported by the high vitrinite contents, moderate ash yields, and high total sulfur contents. The high ash and carbonaceous shale benches probably represent either periods of dryness and substrate exposure, or flooding of the mire surface, the duration of which is unknown. 04/00016 Petrology and geochemistry of the high-sulphur coals from the Upper Permian carbonate coal measures in the Heshan Coalfield, southern China Shao, L. et al. International Journal IJ~ Coal Geology, 2003, 55, (1) l26. The Heshan coals, with very high organic sulfur content, are found in the Upper Permian marine carbonate successions (Heshan Formation) in the Heshan Coalfield, central Guangxi, southern China. The petrography, mineralogy, and geochemistry of coals and non-coal partings from the Suhe and Lilan coal mines of the Heshan Coalfield have been investigated using proximate, petrographic, inductively coupled plasma mass spectrometry (ICP-MS), X-ray fluorescence (XRF), X-ray diffraction (XRD), and scanning electron microscopy with an energy-dispersive X-ray (SEM-EDX) techniques. The sulfur content in the coals (with ash less than 50%) ranges from 5.3% to 11.6%, of which more than 90% is organic sulfur, reflecting a strong marine water influence on the palaeomire. The high vitrinite reflectance (1.89-2.18%Ro,,,) indicates that the coals in the Heshan Coalfield are mainly low-volatile bituminous coal. Microscopic observation has revealed that the coal is mainly composed of vitrinite and inertinite macerals with relatively low TPI and high GI values, suggesting an unusual, strongly alkaline palaeomire, with high pH. XRD analysis plus optical and scanning electron microscopy show that the minerals in these coals are mainly quartz, calcite, dolomite, kaolinite, illite, and pyrite, although marcasite, strengite, and feldspar, as well as some oxidized weathering products such as gypsum, are also present. Most trace elements in the Heshan coals are enriched with respect to their world mean, with MO, U, and W highly enriched, more than 10 times their world means. The trace elements are believed to be associated either with organic compounds (MO and U) or minerals such as aluminium-iron-silicates (SC, Ge, and Bi), aluminium-silicates (Cs, Be, Th, Pb, Ga, and REE), iron-phosphates (Zn, Rb, and Zr), ironsulfides (As, Cd, Cr, Cu, Ni, Tl, and V), and carbonates (Sr, Mn, and W). Abnormally high organic sulfur content, high ash yields, relatively high GI values, very low TPI values, very high U contents, and very low ThAJ ratios suggest that the Heshan coals accumulated in low-lying, marine-influenced palaeomires, developed on carbonate platforms. Many of these characteristics have also been recorded in the Tertiary coals of the circum-Mediterranean coal basins, where no marine influence is present. The similarities are thought to be produced by strongly alkaline groundwater chemistry, common to both environments. 04/00017 Study on combustion characteristics of coal by TG-DSC-FTIR Zou, X. et al. Meitan Zhuanhua, 2003, 26, (l), 71-73. (In Chinese) The combustion characteristic of high sulfur coal from Sichuan was studied by using the combination of thermogravimetry (TG) and FTIR in this paper. The TG experiments were carried out for coal combustion at increasing temperature rates (10”min, 20”min, 30”min) and the relation curves of the active energy and the mass loss of coal were obtained. 04100019 The geology, petrology, palynology and geochemistry of Permian coal basms in Tanzania 2. SongweKiwira Coalfield Semkiwa, P. et al. International Journal of Coal Geology, 2003, 55, (24), 157-186. This study provides coal quality, petrological, palynological and geochemical (Rock Eval) data on Permian coal seams and associated shales and mudstones of the Karoo Supergroup of the Songwe-Kiwira Coalfield, Tanzania. The coal seams, which have a cumulative thickness of 6.80 m, occur in the shale-coal-sandstone facies of the Mchuchuma Formation of Artinskian to Kungurian(?) age. Coal quality data (calorific values, volatile matter contents) and vitrinite reflectances indicate high volatile C bituminous to high volatile A bituminous coals, 4
Fuel
and
Energy
Abstracts
January
2004
having relatively high ash yields (22-49 wt%) and highly variable sulfur contents (0.17-9.2 wt%). They could be used to fuel small-scale power generation units thereby providing electricity to nearby towns and villages. Also, the coals could be used as a substitute for wood, which is becoming increasingly scarce. In rural Tanzania, charcoal is still the main energy source for cooking, and wood is used extensively in brick kilns and for making roofing tiles. Petrological analysis indicated that the coals are dominated by dull to banded dull lithotypes, with seams at the base of the Mchuchuma Formation enriched in inertinite macerals (up to 83 vol%), whereas up-section vitrinite contents increase. Palynological analyses indicated that the assemblage in the lower Mchuchuma Formation (Scheuringipollenites assemblage) is dominated by trilete spores, whereas in the remainder of the section, non-taeniate disaccates dominate (Scheuringipollenites-Protohaploxypinus assemblage). Facies critical macerals suggest for most seams a marsh/wet forest swamp depositional setting, which is consistent with the palynological data. Rock Eva1 analyses indicate type II/III kerogen, with T,,, (“C) values ranging from 426 to 440, corresponding to the early stage of hydrocarbon generation. Thermal alteration indices (2 to 2+) and vitrinite reflectance levels (0.60-0.83 Ro (%)) support the Rock Eva1 maturity assessment, and despite the predominance of terrestriBl-derived organic matter, there is evidence of oil generation and expulsion in the form of cavity and fracture filling exsudatinite. 04/00019 Two thousand years of atmospheric rare earth element (REE) deposition as revealed by an ombrotrophic peat bog profile, Jura Mountains, Switzerland Krachler, M. et al. Journal of Environmental Monitoring, 2003, 5, (1) 111-121. A peat core from a Swiss bog represents 2110 14C years of peat accumulation and provides a continuous record of atmospheric rare earth element (REE) deposition. This is the first study providing a time-series of all REE originating from the atmosphere. Concentrations of the 114 REE (La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu) were detected using inductively coupled plasma-mass spectrometry (ICP-MS) after dissolution of 200 mg aliquots of agedated peat samples with 3 mL HNOs and 0.1 mL HBF4 at 240°C in a microwave autoclave. Strict quality control schemes were applied to ensure the accuracy of the applied analysis methodology. Previous analyses of selected REE by instrumental neutron activation analysis (INAA) in the same set of peat samples revealed that INAA frequently under- or overestimated REE concentrations in a systematic manner. Concentration profiles obtained for all REE were almost identical, except for Ce and Eu. Calculation of enrichment factors (EF) revealed a distinct depletion of heavy REE relative to light REE in peat samples since the beginning of the 19th century, which marks the onset of the Industrial Revolution in Europe, suggesting a pronounced influence by anthropogenic activities. Enrichments of REE calculated using SC as a reference element exceeded unity, relative to the Upper Continental Crust. Overall, EF in all peat samples ranged from 1.96 for Sm to 2.34 for Gd, with considerably lower EF for Ce (1.82) and Eu (1.44), respectively. A significant enrichment of all REE which may have been caused by military activities, was observed in the peat sample dating from World War II (1944); this exceptional sample, however, is not enriched in Ce. The concentration profiles of REE were similar but not identical to those of other lithogenic, conservative reference elements such as SC, Y, Al, Zr and Ti. Whereas it has been suggested that individual REE concentrations or the sum of REE can be used as a reference parameter to calculation crustal EF in environmental samples the data presented here indicates that anthropogenic emissions of REE cannot simply be ignored.
Preparation 04/00020 A plant comparison of the vorsyl separator and dense medium cyclone in the treatment of Indian coals Banerjee, P. K. et al. International Journal of Mineral Processing, 2003, 69, (l-4) 101-114. In India, a major portion of metallurgical coal of desirable ash is produced from the dense medium cyclone (DMC) process. Based on detailed laboratory studies, vorsyl separator (VS), a centrifugal dense medium separator, was established to be a possible alternative to the dense medium cyclone. To establish further at compound scale, trials were undertaken with 400 and 600-mm vorsyl separators made of mild steel, at the captive washeries of the Tata Iron and Steel. The studies clearly showed that the VS gave -5% higher combustible recovery compared to a DMC at the same ash rejection level. Generalized E, value of 0.033-0.045 for VS was also found lower compared to 0.0430.068 for DMC. This clearly established the better sharpness of separation in VS compared to DMC. Vorsyl separator made of suitable wear-resistant material is recommended for regular plant use.
fuels
(preparation)
all other plant groups are minor in comparison. Petrographically, the Sewickley coal contains high percentages of vitrinite (average 82.3%, mineral matter-free (mmf)), with structured forms being more common than unstructured forms. In contrast, liptinite and inertinite macerals both occur in low percentages (average 7.7% and lO.O%, respectively). Geochemically, the Sewickley coal has a moderate ash yield (average 12.4%) and high total sulfur content (average 3.4%). Four localities contained a high ash or carbonaceous shale bench. These benches, which may be coeval, are strongly dominated by tree fern spores, Unlike the lower ash benches, they contain low percentages of vitrinite, which mainly occurs as unstructured vitrinite, and higher liptinite and inertinite contents. The accumulated data suggest that the Sewickley paleomire was probably a rheotrophic, planar mire that had a consistent water cover. This is supported by the high vitrinite contents, moderate ash yields, and high total sulfur contents. The high ash and carbonaceous shale benches probably represent either periods of dryness and substrate exposure, or flooding of the mire surface, the duration of which is unknown. 04/00016 Petrology and geochemistry of the high-sulphur coals from the Upper Permian carbonate coal measures in the Heshan Coalfield, southern China Shao, L. et al. International Journal IJ~ Coal Geology, 2003, 55, (1) l26. The Heshan coals, with very high organic sulfur content, are found in the Upper Permian marine carbonate successions (Heshan Formation) in the Heshan Coalfield, central Guangxi, southern China. The petrography, mineralogy, and geochemistry of coals and non-coal partings from the Suhe and Lilan coal mines of the Heshan Coalfield have been investigated using proximate, petrographic, inductively coupled plasma mass spectrometry (ICP-MS), X-ray fluorescence (XRF), X-ray diffraction (XRD), and scanning electron microscopy with an energy-dispersive X-ray (SEM-EDX) techniques. The sulfur content in the coals (with ash less than 50%) ranges from 5.3% to 11.6%, of which more than 90% is organic sulfur, reflecting a strong marine water influence on the palaeomire. The high vitrinite reflectance (1.89-2.18%Ro,,,) indicates that the coals in the Heshan Coalfield are mainly low-volatile bituminous coal. Microscopic observation has revealed that the coal is mainly composed of vitrinite and inertinite macerals with relatively low TPI and high GI values, suggesting an unusual, strongly alkaline palaeomire, with high pH. XRD analysis plus optical and scanning electron microscopy show that the minerals in these coals are mainly quartz, calcite, dolomite, kaolinite, illite, and pyrite, although marcasite, strengite, and feldspar, as well as some oxidized weathering products such as gypsum, are also present. Most trace elements in the Heshan coals are enriched with respect to their world mean, with MO, U, and W highly enriched, more than 10 times their world means. The trace elements are believed to be associated either with organic compounds (MO and U) or minerals such as aluminium-iron-silicates (SC, Ge, and Bi), aluminium-silicates (Cs, Be, Th, Pb, Ga, and REE), iron-phosphates (Zn, Rb, and Zr), ironsulfides (As, Cd, Cr, Cu, Ni, Tl, and V), and carbonates (Sr, Mn, and W). Abnormally high organic sulfur content, high ash yields, relatively high GI values, very low TPI values, very high U contents, and very low ThAJ ratios suggest that the Heshan coals accumulated in low-lying, marine-influenced palaeomires, developed on carbonate platforms. Many of these characteristics have also been recorded in the Tertiary coals of the circum-Mediterranean coal basins, where no marine influence is present. The similarities are thought to be produced by strongly alkaline groundwater chemistry, common to both environments. 04/00017 Study on combustion characteristics of coal by TG-DSC-FTIR Zou, X. et al. Meitan Zhuanhua, 2003, 26, (l), 71-73. (In Chinese) The combustion characteristic of high sulfur coal from Sichuan was studied by using the combination of thermogravimetry (TG) and FTIR in this paper. The TG experiments were carried out for coal combustion at increasing temperature rates (10”min, 20”min, 30”min) and the relation curves of the active energy and the mass loss of coal were obtained. 04100019 The geology, petrology, palynology and geochemistry of Permian coal basms in Tanzania 2. SongweKiwira Coalfield Semkiwa, P. et al. International Journal of Coal Geology, 2003, 55, (24), 157-186. This study provides coal quality, petrological, palynological and geochemical (Rock Eval) data on Permian coal seams and associated shales and mudstones of the Karoo Supergroup of the Songwe-Kiwira Coalfield, Tanzania. The coal seams, which have a cumulative thickness of 6.80 m, occur in the shale-coal-sandstone facies of the Mchuchuma Formation of Artinskian to Kungurian(?) age. Coal quality data (calorific values, volatile matter contents) and vitrinite reflectances indicate high volatile C bituminous to high volatile A bituminous coals, 4
Fuel
and
Energy
Abstracts
January
2004
having relatively high ash yields (22-49 wt%) and highly variable sulfur contents (0.17-9.2 wt%). They could be used to fuel small-scale power generation units thereby providing electricity to nearby towns and villages. Also, the coals could be used as a substitute for wood, which is becoming increasingly scarce. In rural Tanzania, charcoal is still the main energy source for cooking, and wood is used extensively in brick kilns and for making roofing tiles. Petrological analysis indicated that the coals are dominated by dull to banded dull lithotypes, with seams at the base of the Mchuchuma Formation enriched in inertinite macerals (up to 83 vol%), whereas up-section vitrinite contents increase. Palynological analyses indicated that the assemblage in the lower Mchuchuma Formation (Scheuringipollenites assemblage) is dominated by trilete spores, whereas in the remainder of the section, non-taeniate disaccates dominate (Scheuringipollenites-Protohaploxypinus assemblage). Facies critical macerals suggest for most seams a marsh/wet forest swamp depositional setting, which is consistent with the palynological data. Rock Eva1 analyses indicate type II/III kerogen, with T,,, (“C) values ranging from 426 to 440, corresponding to the early stage of hydrocarbon generation. Thermal alteration indices (2 to 2+) and vitrinite reflectance levels (0.60-0.83 Ro (%)) support the Rock Eva1 maturity assessment, and despite the predominance of terrestriBl-derived organic matter, there is evidence of oil generation and expulsion in the form of cavity and fracture filling exsudatinite. 04/00019 Two thousand years of atmospheric rare earth element (REE) deposition as revealed by an ombrotrophic peat bog profile, Jura Mountains, Switzerland Krachler, M. et al. Journal of Environmental Monitoring, 2003, 5, (1) 111-121. A peat core from a Swiss bog represents 2110 14C years of peat accumulation and provides a continuous record of atmospheric rare earth element (REE) deposition. This is the first study providing a time-series of all REE originating from the atmosphere. Concentrations of the 114 REE (La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu) were detected using inductively coupled plasma-mass spectrometry (ICP-MS) after dissolution of 200 mg aliquots of agedated peat samples with 3 mL HNOs and 0.1 mL HBF4 at 240°C in a microwave autoclave. Strict quality control schemes were applied to ensure the accuracy of the applied analysis methodology. Previous analyses of selected REE by instrumental neutron activation analysis (INAA) in the same set of peat samples revealed that INAA frequently under- or overestimated REE concentrations in a systematic manner. Concentration profiles obtained for all REE were almost identical, except for Ce and Eu. Calculation of enrichment factors (EF) revealed a distinct depletion of heavy REE relative to light REE in peat samples since the beginning of the 19th century, which marks the onset of the Industrial Revolution in Europe, suggesting a pronounced influence by anthropogenic activities. Enrichments of REE calculated using SC as a reference element exceeded unity, relative to the Upper Continental Crust. Overall, EF in all peat samples ranged from 1.96 for Sm to 2.34 for Gd, with considerably lower EF for Ce (1.82) and Eu (1.44), respectively. A significant enrichment of all REE which may have been caused by military activities, was observed in the peat sample dating from World War II (1944); this exceptional sample, however, is not enriched in Ce. The concentration profiles of REE were similar but not identical to those of other lithogenic, conservative reference elements such as SC, Y, Al, Zr and Ti. Whereas it has been suggested that individual REE concentrations or the sum of REE can be used as a reference parameter to calculation crustal EF in environmental samples the data presented here indicates that anthropogenic emissions of REE cannot simply be ignored.
Preparation 04/00020 A plant comparison of the vorsyl separator and dense medium cyclone in the treatment of Indian coals Banerjee, P. K. et al. International Journal of Mineral Processing, 2003, 69, (l-4) 101-114. In India, a major portion of metallurgical coal of desirable ash is produced from the dense medium cyclone (DMC) process. Based on detailed laboratory studies, vorsyl separator (VS), a centrifugal dense medium separator, was established to be a possible alternative to the dense medium cyclone. To establish further at compound scale, trials were undertaken with 400 and 600-mm vorsyl separators made of mild steel, at the captive washeries of the Tata Iron and Steel. The studies clearly showed that the VS gave -5% higher combustible recovery compared to a DMC at the same ash rejection level. Generalized E, value of 0.033-0.045 for VS was also found lower compared to 0.0430.068 for DMC. This clearly established the better sharpness of separation in VS compared to DMC. Vorsyl separator made of suitable wear-resistant material is recommended for regular plant use.